This grant is aimed at facilitating the continued involvement of investigators at the University of Minnesota in the multi-institutional cooperative therapeutic and non-therapeutic studies conducted by the Childrens Cancer Group (CCG). During the past five years, the University of Minnesota has maintained its role as a leading institution in CCG, both logistically and scientifically. Since 1983, there has been a 50% increase in the number of patients placed on study by the University of Minnesota network such that by 1992 over 125 new patients are expected on 1st line studies and 1,117 patients will be in active follow-up, placing the University of Minnesota third among CCG's 33 principal institutions in both categories. Scientifically, the University of Minnesota investigators have been leaders in various aspects of CCG studies, including treatment of acute lymphocytic leukemia, acute myeloid leukemia, and neuroblastoma; investigation of new agents and pharmacokinetics of anti-cancer drugs; bone marrow transplantation for leukemia, neuroblastoma, and other childhood solid tumors; radiation therapy, including total body irradiation; characterization of cancer cells, including cytogenetics and cell surface antigen determinations; cancer epidemiology; and studies investigating the late effects of childhood cancer and its treatment. Twenty-one University of Minnesota investigators hold positions on CCG study committees, strategy groups, scientific committees, discipline committees, or administrative committees. Furthermore, 15 of these investigators have been chairpersons of various CCG committees, documenting that the University of Minnesota is among the top CCG institutions in scientific leadership. CCG studies are conducted using a "team approach" which involves individuals from a wide range of disciplines including oncologists, radiation therapists, surgeons, immunologists, pathologists, cytogeneticists, pharmacologists, and epidemiologists. University of Minnesota investigators are involved in virtually all areas of CCG interest and our involvement in future CCG studies will continue to grow. This grant requests personnel support for Minnesota investigators and personnel key to the maintenance of effective data management and quality control for CCG studies; travel for Minnesota investigators; and miscellaneous expenses for administering our continued involvement in both scientific input and the direction, planning, development, and conduct of clinical investigation and ancillary studies to be conducted by the Childrens Cancer Group.